Thursday, February 21, 2013

I am taking time out from my "Around the World" trip and writing from Luxor, Egypt where I visited King Tut's tomb today. Many friends, colleagues and one very special wife have written to me to share news of a giant slump that has closed State Highway 89 between Flagstaff and Page, Arizona. The Arizona Department of Transportation (ADOT) is calling this a "geologic event", one that occurred on the morning of February 20 (local Arizona time). You can read the AP story and see pictures of the failed road bed here. See also Arizona State Geologist Lee Allison's blog and descriptions by Jon Spencer here. Additionally, ADOT has already produced an informative and image-rich video describing in engineering terms what happened to the road and what it might take to fix it (thanks to John P. for providing this link to me).

I can give an informal geological assessment of the rock failure as I travel that road often and am familiar with the geologic setting of that portion of the highway. It is one of the most scenic roads in all the state of Arizona.

View from Highway 89 looking west toward the upper part of the Grand Canyon, known as Marble Canyon. The slump area is located just left of this shot and earlier slump deposits are visible in the foreground. The large boulders are collapsed fragments of Navajo Sandstone that fell from the Echo Cliffs (behind the photographer) from the previous slumping events. Photo taken in November, 2007

View to the south of the Echo Cliffs (photo taken in winter, 2010). The older slump is also visible in the foreground and is a part of the recent slump area.

Great view of slump material which is common on this slope. The slump was caused by cohesion failure in the Triassic Chinle Formation. Anyone who travels Highway 89 north of Cameron will know the havoc that this shale and mudstone lithology creates in the bed of that highway. Motorists often "enjoy" a free massage since the clays and shales swell when wet, then contract as they dry.

The Chinle Formation exposed north of Cameron Arizona, displaying the soft nature of the shale, claystone and mudstone bedding. Photo taken on October 17, 2009.

Chuck LaRue of Flagstaff sent me this Google image of Highway 89 and the previous slump is quite visible from this vantage. Note how the white colored Navajo Sandstone clearly has slumped downslope just above the highway in this view. Note that road construction in the late 1950's curved around the westward protrusion of the slump material.

Same image with lines highlighting the prehistoric slump area. The solid red line shows where the rocks broke away from, the dashed yellow line is the top of the slump block. This mass of rock slid downslope about 250 to 300 feet. The age of slumping is unknown to me.

A 'Halfway Around The World' Assessment - As I can believe, ADOT geo-engineers are on site evaluating options. Some rumors suggest that the highway may closed up to one year. The bed failure of the highway necessitates a tedious detour around the slump to State Highway 98, making a trip from Flagstaff to Page some 50 miles farther. Some brave travelers may try the unpaved Coppermine Road but likely just once if they do (the road is quite bumpy). I am sure that one viable option is to quickly pave the Coppermine Road. Some have also said that maybe the "slump route" may be abandoned. Not likely.The road is too scenic and too direct for that and engineers rarely say, "We give up" these days. Look for a massive stabilization project on this slope, very similar to that undertaken on the Mesa Verde approach road in southwestern Colorado. (There huge portions of the Cretaceous Mancos Shale have often slipped, yet the National Park Service has completed very expensive and a well-engineered solution there (see here). ADOT will do the same here, hopefully that will be landscape interpretive friendly, and we will be able to one day travel this great road again. However, this slope will also one day again slide downhill as it has for at least the last several hundred thousand years.

Thanks for a very factual discussion of the slope failure (engineering term) on Highway 89. It's often described as a "sinkhole" which is not at all accurate. I was disappointed a few years ago when ADOT summarily dismissed the idea of paving Coppermine Road through to Gap and designating it either a state or county highway. Now the chickens have come home to roost. IF we are looking at a year to reopen Highway 89, paving Coppermine as an interim alternate is a very good idea.

Thank you so much for taking time out from your world tour to explain this! I have been posting this on my Facebook page and was happy to share your blog post with them to explain the story behind the "split."

About Me

I am a geologist, a writer, a river and trail guide and a traveler. Everything seems right when I am on a trail or river watching the earth spin - my cares and worries disappear, my body and mind get exercise, and there is nothing to disturb the ebb and flow of life. Out there is where ideas come to me, where stories flow through me like the rivers that carry me towards home. Now and then, I post ramblings on geology, life in the west and on a living planet,\ and travels across the globe. Life is good, if only we'd take the time to understand that.

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All In A Days Karma

Thank you for visiting my geology blog! If you enjoyed the blog posts here, you may also be interested in seeing my personal blog called All In A Days Karma. I created this blog in February, 2011 because many friends and readers have requested something a little less scientific with more adventure and observational ramblings. Check it out here.

The Grand Canyon...

I lead geology- and hiking-themed river trips in the Grand Canyon

I Have Served As An On Camera Geologist In Seven Documentaries

This photo is from a helicopter shoot over Canyonlands in 2009 for a National Geographic TV documentary. Other shoots were for The Discovery Channel, The History Channel, PBS Phoenix, and others

San Francisco Peaks Stratovolcano

North of the San Francisco Peaks near my hometown in Flagstaff, Arizona

A Colorado Plateau Look-Alike

Believe it or not in southern Pakistan

Lonquimay Volcano and Auraucaria trees in Chile

My work takes me all over the world...

In Front of an Argentinian Glacier

Puerto Moreno Glacier, January, 2008

At the pyramids

Giza in Egypt

Mt. Everest in the Himalaya

In 2007 I climbed with friends to the Everest Base Camp

I have been to Africa many times and love it

A hippo enjoys an afternoon swim in Queen Eizabeth National Park, Uganda

In the Galapagos

Unique volcanic islands

Esfahan, Iran

An interesting and beautiful place

I Lecture on Private Jet Trips Around the World

The Explorer jet on the tarmac in Brazil

Argentina and the Andes Mts.

The Perito Moreno Glacier

Ama Dablam in the Himalaya's

On a trek to Kala Patthar, Nepal

The Fisher Towers near Moab,Utah

I love Southwestern Geology!

Earthly Musings

I hope you like this blog - I sure enjoy writing it. As anyone who blogs will know, it is difficult to write all of the time. When I'm out on a trip it is impossible to go online but when I return home, I will have pictures to post. I appreciate you looking in now and then, and seeing what I am up to. Thank you.